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instrument mechanism / verified-clean
Normality / Equivalents Calculator mechanism
The inspectable method record for Normality / Equivalents Calculator, kept separate from implementation and qualification.
Model scope
The arithmetic formula is correct, and the stated legacy-unit label is appropriate. Review is required because automatic lookup from an acid/base formula is underspecified for endpoint-dependent acid-base chemistry and medium-dependent redox chemistry.
- N = M × n_eq is the standard formula when M is mol/L and n_eq is the reaction-specific equivalents per mole.
- An equivalence factor cannot always be determined from an acid/base formula alone: polyprotic acids such as H3PO4 have different factors depending on the titration endpoint.
- Redox equivalence factors depend on the reaction and medium; for example, permanganate has different electron factors in acidic, neutral, and alkaline solution.
- The lookup table must record the reaction context or endpoint, not only the chemical formula.
Units and conventions
- Molarity M is moles of solute per litre of final solution (mol/L).
- The equivalence factor n_eq is equivalents per mole and is dimensionless as used in N = M × n_eq.
- The output unit is equivalents per litre (eq/L), commonly written as normality (N).
- If concentration is supplied in mmol/L, it must be converted to mol/L before applying the formula.
- For acid-base reactions, the selected n_eq assumes a stated titration endpoint; for redox reactions, it assumes a stated medium and balanced reaction.
Inspectable vector
One of 4 source-bound review vectors:
{
"inputs": {
"solute": "HCl",
"molarity": 0.1,
"molarity_unit": "mol/L",
"equivalence_factor": 1,
"basis": "one H+ neutralized per HCl molecule"
},
"expected_outputs": {
"normality": 0.1,
"normality_unit": "eq/L"
},
"working": "N = M × n_eq = 0.1000 mol/L × 1 eq/mol = 0.1000 eq/L."
}Failure boundary
BREAK_CLAIMED · SELF_FLAGGED
The extreme-magnitude vector causes JavaScript multiplication to overflow: 1e308 × 1e308 becomes Infinity. The instrument should validate finite numeric inputs and reject or clearly report the non-finite result.
Other records
Sources and evidence
These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.
VERIFIED_LEDGER.jsonevidence-tranche6/tranche6-results.jsonBOUNDARY_HAZARD_CATALOG.json